A game classified as a combat flight simulation has been known in which the player operates an aircraft such as a fighter aircraft and attacks an enemy. The player enjoys the game by operating a fighter aircraft (i.e., player character) as a mercenary pilot or a regular force pilot, and attacking an enemy aircraft or an enemy ground weapon to accomplish operations assigned to the player.
In recent years, technology has been known in which a fighter aircraft (player character) operated by the player and a plurality of friend aircraft automatically controlled by a computer organize a military force, and the player plays the game while issuing instructions to the friend aircraft (see JP-A-2005-224281, for example). Specifically, the friend aircraft are normally controlled to be distributed in a game space and to search for and attack an enemy. When the player has performed a gather instruction operation input, the friend aircraft are controlled to gather around the player character. When the player has performed an attack instruction operation input, the friend aircraft are controlled to selectively search for and attack an enemy within an attack range in front of the player character. Specifically, the player can not only enjoy a fighter aircraft flight simulation, but also enjoy a realistic situation in which the player fights a battle while receiving support from the friend aircraft.
In order to make the combat flight simulation game more realistic, it is desirable to employ large-scale military operations in which a number of weapons deployed over a wide area participate. It is also desirable that the player fight a battle while cooperating with friend characters instead of taking independent action in the operation area.
The technology disclosed in JP-A-2005-224281 may be applied to a number of friend non-player characters (NPCs) deployed over a wide area so that the player can cooperate with friend characters. According to the technology disclosed in JP-A-2005-224281, the friend aircraft operate based on instructions from the player. Therefore, a situation in which the player and the friend aircraft help each other in a battlefield cannot be implemented.